Answer:
The Incas focused on innovations in agriculture, while Aztecs focused on transportation.
It depends on the shape of the stones. If the stones are in the shape of an arrowhead, then yes, they are evidence of early humans. If not, it could be just a piece of broken rock.
The world was rapidly developing after world war 2 and with these new innovations, new responsibilities grew. For example, female employment and race issues were a large issue in post WW2 USA and governments had to adapts to accept equality and ongoing change.
One of the major effects of the cotton gin on slavery was the increased need for slaves ... With Eli Whitney's invention, cotton lint could be produced quickly and ... far less painful, the increased demand for slaves resulted in slavery raising from ... effects of the Western Expansion in the United States were the intensification of
